Mr Shabbir Mohamed
Ophthalmology

What to expect from the iStent® implant for glaucoma

Written by: Mr Shabbir Mohamed

Published: 10/02/2020

Edited by: Laura Burgess

For patients who have mild to moderate glaucoma, the iStent® can be implanted to help lower eye pressure. Following surgery, many patients can reduce the number of eye drops they use to treat their glaucoma. Mr Shabbir Mohamed was one of the first ophthalmic surgeons to pioneer the procedure over a decade ago via his service in Birmingham. Here he explains what happens during the procedure, if there are any risks and how recently it has advanced even more.

Older lady sat smiling, wearing glasses

What is the iStent®?

The iStent® is a tiny device (0.2mm x 0.3mm) that is implanted into your eye. Its job is to help control eye pressure and treat glaucoma thereby preserving vision. It tends to be implanted at the time of cataract surgery in patients who have glaucoma as a combined procedure but can also be used as a standalone device in certain selected cases. The role of the iStent® is to reduce the chances of the patient needing more invasive and risky procedures.

What is your experience with the iStent®?

In the West Midlands, I was one of the pioneers of iStent® back in 2009. I have been using it in cases here ever since for the last ten years. I have implanted it in numerous patients with different types and severity of glaucoma with good results. For some patients, it has been really helpful in saving their eyesight from being lost due to glaucoma.

How can I prepare for the procedure?

iStent® implantation is a procedure that is recommended by ophthalmologists in patients whose glaucoma is not adequately controlled on medication. It is a surgical procedure that is relatively minor for the person but is a significant intervention for the eye. It is less invasive than other types of glaucoma surgery. We call it a minimally invasive glaucoma surgical (MIGS) procedure. In terms of preparation, you don’t have to do anything specific.

What happens during the procedure?

Usually, the iStent® is implanted at the time of cataract surgery and often the patient would have a numbing injection (local anaesthetic) around the eye. The procedure is performed in the operating theatre in a sterile environment. The patient would lie on a surgical table and the painless procedure takes about ten minutes if it is a stand-alone procedure and if combined with cataract surgery, about 30 minutes.

Will I be able to see or feel the device once implanted?

The patient will not be able to feel or see the implanted iStent® as it is tiny measuring about 0.2mm x 0.3mm. It sits inside the eye and so you would not feel it at all.

What happens during recovery?

The risks of the procedure include risk of infection and bleeding and we obviously take steps to minimise these from happening. iStent® implantation doesn’t tend to affect vision. If the patient could drive before, they should be able to after within a couple of days. They would just need to use the eye drops that are prescribed. We like to review our patients on the first day, after one week and also one month after the procedure.

Are there any risks of the iStent®?

There are the standard risks of infection and bleeding and occasionally the iStent® can move. This can cause difficulty in implanting and it might need to be repositioned in a secondary procedure. The risk is less than 1 in 100 in my practice. Sometimes the stent does not work and in about 15-20 per cent of cases, the pressure doesn’t come down after implanting the iStent®. This means that the patient might need another procedure.

How do I know if I am a suitable candidate?

iStent® is ideally suited to patients who have mild to moderate glaucoma and whose eye pressure is not controlled on their current medical treatment (eye drops). It works very well when combined with cataract surgery, therefore, patients undergoing cataract surgery, who also have glaucoma, should have iStent® put in at the time of their surgery.

There is a newer version of the iStent®, which is known as the iStent inject®. The latest version of the procedure has been around for about 18 months and you have two stents for the price of one. It is more straightforward, cost-effective and less risky than the original iStent®.

Ophthalmology in Birmingham

Mr Shabbir Mohamed is a highly skilled ophthalmologist based in Birmingham and the West Midlands, who specialises in treating cataracts, glaucoma, and ocular surface disease, among other eye conditions. He treats patients with medical and surgical techniques, including the use of laser technology. He is an innovator, developing creative ways of delivering top quality care to his patients. Mr Mohamed qualified in medicine from Manchester Medical School (University of Manchester) in 1996, befor...

By Mr Shabbir Mohamed
Ophthalmology

Mr Shabbir Mohamed is a highly skilled ophthalmologist based in Birmingham and the West Midlands, who specialises in treating cataracts, glaucoma, and ocular surface disease, among other eye conditions. He treats patients with medical and surgical techniques, including the use of laser technology. He is an innovator, developing creative ways of delivering top quality care to his patients.

Mr Mohamed qualified in medicine from Manchester Medical School (University of Manchester) in 1996, before training in general ophthalmology in the West Midlands. He then completed advanced training in glaucoma and the management of corneal and external disease. He is fellow of the Royal College of Surgeons of Edinburgh and the Royal College of Ophthalmologists.

Mr Shabbir Mohamed has successfully established a community ophthalmic clinic at the Sutton Medical Consulting Centre and developed a complex glaucoma service at University Hospital Birmingham. His philosophy is that caring for patients and easing their pain is a privilege and is keen to ensure that his service is top quality. To this end, he prospectively audits his surgical service to ensure that standards are maintained, and participates in regular surveys of patient satisfaction. This, combined with his research into developing new treatments and optimising patient outcomes, makes him a leader in his field.